Print Friendly Version of this pagePrint Get a PDF version of this webpagePDF

SolaStay® S1

INCI Name: Ethylhexyl Methoxycrylene
Product Code: H044
CAS #: 947753-66-4
Patents: 7,588,702; 7,597,825; 7,713,519; 7,754,191; 7,959,834; 8,070,989; 8,075,808; 8,133,477; 8,257,687; 8,263,050; 8,263,051; 8,268,294; 8,278,332; 8,329,148; 8,431,112. Patents Pending.
Brand: SolaStay®

SolaStay® is a viscous yellow liquid designed for use in skin care and sun care products. It is a highly efficient singlet state quencher for butyl methoxydibenzoylmethane (avobenzone) and ethylhexyl methoxycinnamate (octinoxate). Indeed, it outperforms octocrylene as an avobenzone photostabilizer, photostabilizes octinoxate and avobenzone when formulated together, is an outstanding solvent for crystalline UV filters, is easily emulsified, and is suitable for use in lotion, cream, spray, stick, and gel formulations.

At a recommended use level in sunscreens equal to the weight percentage of avobenzone in the formulation (typically 2-3%), SolaStay® S1 enables new heights of performance in broad spectrum UVA and UVB photoprotection. Used at 1-3% with mineral UV filters and/or cosmetic colorants, it mitigates the photocatalytic and reactive oxygen species-generating activities of these oxides.

SolaStay® S1 has also been documented to substantially photostabilize cholecalciferol, resveratrol, retinol, retinyl palmitate, and ubiquinone, which may be incorporated in skin care products for their anti-photoaging and other benefits. The recommended used level for SolaStay® S1 to photostabilize these products is 3-5%.

Features & Benefits:

  • Sunscreen Active Photostabilizer
  • Anti-aging Ingredient Photostabilizer
  • Sunscreen Solvent
Appearance (25°C) Clear yellowish viscous liquid
Color (Gardner) 9
Odor Mild characteristic
Dielectric Constant (25°C) 12.9
Specific Gravity (25°C/25°C) 1.075
Viscosity (cP, 25°C) 13000
Viscosity (cP, 80°C) 58
Acid Value (mg KOH/g) 0.7
Soluble In
  • Alcohol [Ethanol]
  • Cosmetic Esters
Solvency Of
  • 4-Methylbenzylidene Camphor (Enzacamene) 10%
  • Ethylhexyl Triazone 25%
  • Benzophenone-3 (Oxybenzone) 30%
Toxicology Profile
  • Ames Test: No detectable genotoxic activity in absence or presence of S9 enzyme activation.
  • Ocular / Eye Irritation: Practically no ocular irritation potential in vivo at 20% (HET-CAM).
  • Phototoxicity: Did not induce a response indicative of a photoxic reaction.
  • Repeat Insult Patch Test (Human): Did not indicate a potential for dermal irritation or allergic contact sensitization.
  • Drum - 420lbs
  • Pail - 40lbs

Regional Approvals:

  • Canada
  • EU
  • US


  • Acid neutralizer
  • Acid neutralizer
  • Daily Wear Sun Care
  • Acid neutralizer
  • Acid neutralizer


Scroll right to view specs →
Name Regional Acceptance  Formula Number
"No O" Broad Spectrum SPF 30 Cream with SolaStay® S1Canada, EU, USJZ8-164B
3-O-Free Olive Daily Wear Sunscreen Spray SPF 30Canada, EU, USJZ13-109
Absolute Sunscreen Spray SPF 100Canada, EU, USJZ11-300
Absolute Sunscreen Spray SPF 50Canada, EU, USJZ12-24
Absolute Sunscreen Spray SPF 70Canada, EU, USJZ11-299B
Ante-aging Daily Wear SPF 30 Sunscreen SprayCanada, EU, USJZ13-51
Anti-Blue Light Daily Primer SPF 30Canada, EU, USJZ15-60
Anti-Sand Sunscreen Gel SPF 60 US, Canada, EU, Australia, Taiwan, Japan, Philippines, Korea, New Zealand, ASEAN, MERCOSURJZ12-20B
Argan-Hemp Sunscreen Milk SPF 30Canada, EU, USJZ13-35B
Beach Sunscreen Spray SPF 70Canada, EU, USJZ12-167B
Bed Sheet MaskCanada, EU, US131-19-03A
Biphasic 3-O-Free Sunscreen Spray SPF 30Canada, EU, USJZ13-110
Biphasic Sea Glass Spray SPF 30Canada, EU, USJZ13-99
Biphasic Sunscreen Spray SPF 30Canada, EU, USJZ12-304
Broad Spectrum Oil-in-Water Sunscreen Cream SPF 70Canada, EU, USJZ11-73
Broad Spectrum SPF 45 Sunscreen CreamCanada, EU, USJZ5-67
Broad Spectrum SPF 50+ Sunscreen CreamCanada, EU, USJZ6-169
Broad Spectrum Sunscreen Gel SPF 50 PA++++Canada, EU, USJZ11-148B
Clear and Natural SPF 30 Sunscreen Stick with Argan and Hemp OilsCanada, EU, USJZ13-41
Clear SPF 30 PrimerCanada, EU, USJZ13-75
EUphoria Sunscreen SPF 50Canada, EU, USMD21-001-05Z
Everything Bagel SPF 40Canada, EU, USJZ12-20
Facial Moisturizer Cream SPF 50Canada, EU, USJZ14-49B
Fast-Absorbing Sunscreen Spray SPF 50Canada, EU, USJZ12-253
Formulator-Friendly Moisturizing Cream SPF 50ASEAN, EU, Japan, Korea, MERCOSUR, New Zealand, Philippines, TaiwanJZ16-52
Global SPF 50 ZnO Sunscreen StickASEAN, Canada, Japan, Korea, Philippines, Taiwan, USJZ15-44
Harmonious Defense Inorganic Sunscreen SPF 50+ASEAN, Australia, Canada, EU, Japan, Korea, MERCOSUR, New Zealand, Philippines, Taiwan, USJZ15-46B
Know-rish Yourself Daily Moisturizer SPF 15Canada, EU, USCS20-042-01E
Mineral High UV Protection Cream SPF 50Canada, EU, USJZ14-172B
Mineral Only SPF 100, PFA 25 O/W Sunscreen LotionCanada, EU, USJZ11-160
Minerals Only SPF 70, PFA 20 O/W Sunscreen LotionCanada, EU, USJZ11-159
Moisturizer Body Cream SPF 50ASEAN, Australia, Canada, EU, Japan, Korea, MERCOSUR, New Zealand, Philippines, Taiwan, USJZ16-64
Multifunction Daily Stick SPF 30Canada, EU, USJZ14-39
Non-NA Sunscreen Lotion SPF 30Canada, EU, USJZ13-273
Oh Wow! 50 Lotion - Broad Spectrum O-W SPF 50 SunscreenCanada, EU, USRP2-118
Oil Protect You! SPF 30Canada, EU, USJZ15-59
Oil-in-Water Mineral Sunscreen Cream SPF 50Canada, EU, USJZ8-204
Oil-in-Water Sunscreen SPF 20Canada, EU, USJZ5-12
Pink Biphasic Spray SPF 30Canada, EU, USJZ14-45
Polyglyceryl Esters Sunscreen SPF 50ASEAN, Australia, Canada, EU, Japan, Korea, MERCOSUR, New Zealand, Philippines, Taiwan, USJZ16-94
Rosy Spray SPF 30Canada, EU, USJZ15-61
Sheer Blush Sunscreen Stick SPF 30Canada, EU, USJZ14-54
Sheer Daily Wear Mineral Face Lotion SPF 30Canada, EU, USJZ14-242
Silken Sunscreen SPF 30Canada, EU, US100-17-07H
SPF 50 Sunscreen StickCanada, EU, USJZ10-45C
SPF 50 W/O Dream CreamCanada, EU, USJZ14-15
SPF 50 Water-in-Silicone BB CreamCanada, EU, USJZ9-34
Sport Sunscreen SPF 70Canada, EU, USJZ12-207B
Sunlight Bluelight Protection SPF 30Canada, EU, USJZ13-280
Sunscreen Cream SPF 30Canada, EU, USJZ13-269
Sunscreen SPF 50 LotionCanada, EU, USJZ7-116
Sunscreen Stick SPF 50 PA ++++Canada, EU, USJZ11-239
Sunscreen Stick SPF 50 PA++++Canada, EU, USJZ11-219B
Sunshine Stick SPF 30Canada, EU, USJZ13-192
Superior Sunscreen Stick SPF 50 PA ++++Canada, EU, USJZ11-245
Three-O-Free Sunscreen Alcohol Spray SPF 30Canada, EU, USJZ8-150
Unseen Sunscreen SPF 40Canada, EU, USJZ15-131B
Whoa! 50+ Cream - W/O SPF 50+ Mineral SunscreenCanada, EU, USJZ8-215B
Whoa! 50+ Lotion - W-O SPF 50+ Mineral SunscreenCanada, EU, USJZ8-229
ZnO Sunscreen SPF 50Canada, EU, USJZ15-49B
ZnO Sunscreen SPF 60Canada, EU, USJZ15-196B
“No O” Broad Spectrum SPF 30 Sunscreen CreamCanada, EU, USJZ13-105

The information presented herein is believed to be accurate and reliable, but no warranty or guarantee, expressed or implied, is made regarding the information or the performance of any product. Further, nothing contained herein shall be taken as any inducement or recommendation to use, manufacture or sell that may infringe any patents or any other proprietary rights now or hereafter in existence, nor to imply compliance with any regulatory requirements

The Hallstar Company - 120 South Riverside Plaza Suite 1620 - Chicago, IL 60606-3911 USA